Process of making bags



, Nov. '17, 1936. POTDEVIN 2,061,437

PROCESS OF MAKING BAGS Filed Dec. 15, 1952 IN VEN TOR.

ATTORNEYS.

Patented Nov. 17, v 1936 PATENT OFFICE rnooass or MAKING BAGS Adolph Potdevin, Garden City, N. Y.,

Potdevin Machine Company, Brooklyn,

assignor to N. Y., a

corporation of New York ApplicationDecember 15, 1932, Serial No. 647,298 2 Claims. (01. 9335) This invention is directed to a process for the making of bags, and one of the objects of my invention is the provision of a method which is particularly well adapted for the making of bags from cellulose, glassine and such materials which are very difiicult to handle in bag making machines in the ordinary way. 1 I

In the drawing accompanying this application:

Fig. 1 is a diagrammatic plan view of an embodiment of the invention;

Fdli'g. 2 is a sectional elevational view of Fig. 1; an

Fig. 3 is a view in perspective of the completed 35 In-illustrating the invention I have attempted to illustrate more particularly the various steps or operations through which the bag-making material passes in the making of a bag rather than the details of the machine by which the material is handled, inasmuch-as such machines may take various forms.

Referring to the drawing in detail, the material from which the bags are to be made is taken continuously from a supply roll I, the material in web 2 form designated 2 passing from this supply roll about guide roller 3 to an adhesive-applying disc a where a stripe of adhesive shown at 5 in Fig. 1 is applied to the face of the web adjacent one edge thereof.

w After the application of this adhesive the material still in web form is passed between rollers t and l. The roller 1 carries an arcuate slitter 8 and as the web 2 passes between the rollers the slitter cuts arcuate slits 9 in the center of the web at regularly spaced intervals.

The web then passes through tubing mechanism in to be tubed. The tubing mechanism may take the usual form employed in bag making machines and hence has been shown merely diagrammatically.

The tube through forwarding rollers II and past cutting ofi mechanism where it is divided into bag lengths. This cutting off mechanism comprises a fixed member l2 and rotatable striker bar l3.

In severing or dividing thetube into bag lengths, one of which is shown at M, it is to be noted that the lower wall of the leading end is severed transversely to the ends of the arcuate slit 9 to provide a projecting tab l5, while the upper wall of the leading end is cut or severed all the way across as shown at l6 back of or to the rear of the end of the lower wall, so that the 55 lower wall projects beyond the upper wall in the form of a flap ll carrying the tab iii.

The trailing end of the bag length is complementary to the leading end, the upper wall extending below the lower wall to form a flap I8 60 while the trailing end of the lower wall is proas formed passes continuously vided with a notch l9 complementary to the tab [5 at the other end of the bag length.

The bag lengths are continuously forwarded between another pair of rollers 20 to a second severing mechanism comprising'fixed member 2! and rotatable shear bar 22, the latter being so timed as to out off the flap l8 at the trailing end of the bag length, i. e., square the trailing end of the bag length so that this end of the bag length is simply left with the notch iii in it.

The bag length, which is now as shown at 23 in Fig. 1, has adhesive 24 applied to the upper wall thereof at its leading end and the flap l1 and tab l5 are then folded over along the line 25 upon the upper wall of the bag length to bottom the bag as shown in Fig. 3.

What I claim is:-

1. In the making of bags, the method which comprises continuously advancing the bag material in the form of tubing with arcuate slits spaced at regular intervals lengthwise of the tubing in one wall thereof, servering the tubing into bag lengths in predetermined relation to said slits to provide one wall of the leading end of the bag length with a tab-carrying projecting flap, and the trailing end of said wall with a complementary thumb notch, and to provide the trailing end of the opposite wall of the bag length with a flap extending the width of the bag length and projecting beyond the thumb-notched wall, trimming the trailing end of the bag length back of the flap so as to remove the flap and trim the trailing end of both walls of the bag length, so that the edges of this end of the bag length are smooth and unserrated, and then folding over the tab-carrying flap at the leading end of the bag length to bottom the bag.

2. In the making of bags,'the method which comprises continuously advancing the bag material in web form, forming arcuate slits in the advancing web, said slits being spaced at regular intervals lengthwise of the web, tubing the slitted web, severing the tubing into bag lengths in predetermined relation to said slits to provide one wall of the leading end of the bag length with a tab-carrying projecting flap, and the trailing end of said wall with a complementary thumb notch, and to provide the trailing end of the opposite wall of the bag length with a flap extending the width of the bag length and projecting beyond the thumb-notched wall, trimming the trailing end of the bag length back of the flap so as to remove the flap and trim the trailing end of both walls of the bag length, so that the edges of this end of the bag length are smooth and unserrated, and then folding over the tabcarrying fiap at the leading end of the bag length to bottom the bag.

ADOLPH PO'I'DEVIN. 

